In August 2011, Bellisario filed a lawsuit against CBS, seeking unspecified damages for not profiting from the creation of NCIS: LA. Bellisario claims he was not given the first opportunity to develop and participate in the NCIS spin-off, and thus has not profited from it.

The case is scheduled to go to trial on Jan. 14, but CBS has reportedly asked for a trial continuance in order to subpoena Bellisario's medical records and depose his physicians. The network allegedly seeks to prove Bellisario would not have been medically capable to be the showrunner of the NCIS: LA.

Bellisario, 77, suffers from hydrocephalus, otherwise known as "water on the brain," which causes memory loss, disorientation and lack of coordination.

In legal documents, CBS asks: "How long has Bellisario been suffering from this severe brain condition or other severe medical conditions? Are those conditions debilitating? When would they have become debilitating? Would this severe brain condition have prevented Bellisario from adequately performing his duties and responsibilities as showrunner, executive producer and writer of NCIS: Los Angeles? And when would that have occurred?"

CBS, however, denies these allegations. "Mr. Bellisario's medical condition was raised for the first time in his own lawyers' public filings, not by CBS," a spokesman for the network tells TVGuide.com. " We have never attempted to advance our position based on Mr. Bellisario's health, and any suggestion to the contrary is both regrettable and baseless."

Bellisario was let go from NCIS in 2007. Shane Brennan took up the reins on the series and created the NCIS: LA series. NCIS is a spin-off of JAG, which was also created by Bellisario.